Golf club back cavity



FIG. 1 is a perspective view of our new design;

FIG. 2 is a perspective view of our new design;

FIG. 3 is an elevational view of our new design;

FIG. 4 is a heel side elevational view of our new design; and,

FIG. 5 is a top plan view of our new design.

The broken line showing is for illustrative purposes only and forms no part of the claimed design. 

The ornamental design for a golf club back cavity, as shown and described. 